1. Field of the Invention
The present invention relates to mobile devices and, more particularly, to a mobile device with an acoustically-driven handwriting-to-text assembly.
2. General Background
Current manufacturing trends in mobile devices seek to reduce the size of the device so that the user can place the mobile device in an easily accessible location, such as a purse or pocket. Many mobile devices are as small as, or smaller than, a user's hand and are commonly termed “hand-held devices”. Consequently, there are significant size constraints for the display and keypad/navigational tools to be implemented on the limited real estate of such a device.
For example, cellular telephones generally do not provide a fully functional keyboard such as a keyboard with one letter per button. Instead, a numerical keypad is provided with one number per key. The numbered keys may allow three or four alphabetical letters to be entered. However, this type of keypad commonly requires multiple pushes of a single key to enter a single letter. For example, the number “7” key allows a user to enter one of four (4) alphabet letters P, Q, R and S. In order to enter an S, the “7” key is pressed four times. Then, to enter the next letter, the user must either wait for the cursor on the display to move to the immediately adjacent space or press a designated navigational key to move the cursor to the immediately adjacent space. As can be appreciated, this text entering process is tedious, cumbersome and time consuming. The text entering process is one of the potential impediments to the ubiquitous use of the mobile communications device as a versatile digital device.
A touch sensitive screen is one attempt to solve the problem with text input. However, in view of the current manufacturing trends, the size of the touch sensitive screen (with or without a stylus) is insufficient for the screen to provide an accurate mechanism for text input.
Another text input tool is a digital pen. Digital pen technology has an advantage that it does not limit writing to the surface of the screen. However, implementation of a digital pen requires the installation of complex circuitry in the device and other adaptations to provide communications between the device and digital pen.
In general, conventional mobile communication devices do not provide a user with a simple means of entering text such as by simply handwriting one or more alphanumeric symbols with a sound pen on any surface.
Additionally, conventional mobile communication devices do not utilize a microphone for both a speech input mode, such as during a telephone call, and a text input mode where an emitted sound signal from a sound pen is sensed. The sensed sound signal is employed in a pen location tracking process to graphically represent a handwritten alphanumeric symbol.
Furthermore, conventional mobile communication devices do not employ a microphone array that can be employed for noise reduction processing of the speech input signal and, alternately, for a pen location tracking process to graphically represent a handwritten alphanumeric symbol.
Conventional mobile communication devices, such as a cellular telephone, do not employ two display areas where one display area is used to display a graphical representation of a simulated handwritten alphanumeric symbol handwritten or traced on any suitable writing surface.